bad connections in phone joint box giving slower adsl speed

[jondiy]

This is one for the telecoms engineers out there

My adsl broadband connection can vary between 3.5Mbps and 5.5 Mbps just by me opening up a joint box in the house and squeezing the connector blocks with my thumb & forefinger.

The connector blocks looks to be filled with a jelly compound, and the wires that are jointed do not seem sat in tightly.

Would I get a better speed on the line by me pulling the joints from the jel blocks and twisting & soldering & sleeve them, or shall I just get some more gel blocks from ebay and re-make the connections.

Can soldering joins in telephone cable restrict the DSL signal? It does appear that the jel connectors seem more insulated to look at.

 

[Softus]

If it were mine I'd do what you're suggesting, or use connector blocks.

Before you start, have a read of this topic: The connection between the outside BT line and the inside

 

[jondiy]

Cheers Softus

Was wondering whether if soldered, RF might escape through the joint, and poss give crosstalk to the other cores, and slow the connection down. Obviously I'd sleeve them with heatshrink, but just wanted a telecoms engineer to tell me whether having a soldered joint would increase attenuation (which is not good for adsl) , more than it would if I used a gel connector.

Obviously these gel connectors must have been designed to give a fully insulated joint, and hence cause less crosstalk via RF etc.

I'll order some anyway and go experiment, see which method works best.

just for the record , I'm on a MaxADSL product,

 

[Softus]

Was wondering whether if soldered, RF might escape through the joint, and poss give crosstalk to the other cores, and slow the connection down. Obviously I'd sleeve them with heatshrink, but just wanted a telecoms engineer to tell me whether having a soldered joint would increase attenuation (which is not good for adsl) , more than it would if I used a gel connector.

I don't see how a standard amount of insulation will result in more RF than normal, irrespective of what a 'telecomms engineer' might say.

If you don't want to solder the joint, then just connect it in the usual way.

Obviously these gel connectors must have been designed to give a fully insulated joint, and hence cause less crosstalk via RF etc.

I don't know why you regard that as obvious, when I think it's actually incorrect. The gel joint is an effective barrier to moisture, which it's why it's used for joints made outside. It has nothing to do with electrical insulation and especially nothing to do with lowering crosstalk. I suspect that you might even be getting confused, because crosstalk is usually a factor when independent signal paths are bunched together without sufficient screening or balancing.

IMO this is straightforward - either you have a poor joint inside the gel, or you don't. If it's poor then you can just remake it in a normal way, i.e. if it's indoors then without renewing the gel connector. If it's not poor then your belief that putting pressure on the joint changes the ADSL bit rate has no explanation. Yet.

 

[jondiy]

Obviously poor joint, increased resistance on the line hence lower transmission speeds.

Will solder & sleeve it, and see if I can stabilise the bitrate to an acceptable level.

 

[bigzed]

The gel filled connectors you refer to are 8A jointing crimps. We are now replacing as a matter of course, any of the older types ( usually coloured ) as we work on the network. ( Due to them failing certain adsl tests ) If you can squeeze the crimps with your finger and make a better connection, then the crimp is definitely at fault.
They are designed to be closed with a specific tool, which is a pair of parallel jaw pliers. The Petroleum Jelly inside the crimp is, as softus correctly says, just a barrier to the ingress if water, it plays no other part in the working of the joint.
Basically, the crimp is a PJ filled version of the Scotchlock crimps found in car wiring.
If there are no IDC connectors inside the particular Joint Box you are using, I would say that a soldered joint would be at least as good.

 

[JohnJocys]

Be careful when soldering BT wires. It's highly likely that your soldering iron tip will be earthed - the BT network may not take kindly to some of it's cables suddenly being grounded.

 

[bernardgreen]

An earthed soldering iron used to solder a standard domestic BT loop pair will not cause any major problems other than appearing as a earth fault if it is prolonged.

An un-earthed soldering iron could be far more serious if it puts any mains derived voltage onto the pair.

And soldering a drop wire is not always sucessful as some drop wire is plated ( nickel ? ) to reduce corrosion and a good solder joint is difficult to achieve. The joint feels firm but there is no "wetting" of the wire by the solder moisture can get into the joint between the solder and the drop cable wire causing corrosion and eventual failure of the joint.